How can I kill very stubborn and prickly weeds?

Have you tried Round up?

Sounds like wild blackberry. They are horrible and spread by underground risomes everywhere. The only thing I found that works that isn't poison like roundup is solarizing. I had them so bad I had to cover my spaces in heavy black roofing plastic . I use pinestra w or mulch over it and left it that way because nothing, I mean nothing kills it unless you use poison which will kill you and then that BlackBerry will come back ! I just uncovered a few of the areas I covered 2 and 3 years ago and I'm working on grass in these areas, but I still see an occasional small piece lol up and I pull it out by the root. I live in S.C. Also. Every other course I took failed within weeks, including burning it 😤

Thank you you just describing it to a T. I appreciate it so much I am going to try doing what you said and see what happens the trouble is my one neighbor has it in the back of his fence and he is letting it grow free ad it's coming into my fence as well but I'll just keep on chopping that down in front again thank you and covering it like you said

Hi Linda - The struggle is real, isn't it?!? This is the most effective all-natural weed killer DIY that we use. It's even been featured on Hometalk! Hope this helps! Hugs, Holly

https://pinkfortitude.com/weed-killer/

PS - We have a FREE eBook with recipes for all of my homemade and all-natural cleaners. You can download it here --> https://pinkfortitude.com/thank#GreenClean

All the answers with great I've been using hot water with decent results I don't like chemicals so I learned the hard way that you have to use boiling hot water just not hot water and really soak the area then I put cardboard on and put a covering over that of mulch